Preheat oven to 350°F (175°C).
Grease or line a 1 lb loaf pan with parchment paper.
Chop rhubarb into small pieces and set aside.
Cream butter and sugar until smooth and fluffy.
Add eggs one at a time, then mix in vanilla extract.
In another bowl, whisk flour, baking powder, baking soda, and salt.
Gradually add dry ingredients to the batter, alternating with buttermilk.
Fold in chopped rhubarb gently.
Pour batter into the prepared pan and smooth the top.
Sprinkle sugar over the top for a crisp finish.
Bake this Rhubarb Bread Recipe for about 70 minutes, until a toothpick comes out clean.
Cool in pan for 5 minutes, then transfer to a wire rack.